Two Russian companies dominated by multibillionaire eastern European businessmen are expected to be promoted to the FTSE 100 this month.

Their imminent promotion has raised questions about corporate governance and the increasing sway of foreign firms in the City.

The banking group Investec, the satellite company Inmarsat and the platinum producer Lonmin are expected to be ejected from London's premier index after the FTSE listings committee completes its quarterly review tomorrow.

Their places will be taken by the Russian minerals groups Polymetal and Evraz, and the Irish building materials company CRH, because their market values are higher than the companies being relegated.

Evraz's biggest shareholder is Chelsea football club owner Roman Abramovich, who speaks for 35%. Polymetal is dominated by the Russian entrepreneurs Alexander Mamut, the Waterstone's owner, and Alexander Nesis, who own 10% and 17.9% respectively. The Czech investor Petr Kellner controls a further 20.9%.

City shareholders are not happy about the entry of the Russian groups as they tend to dislike firms where big stakeholders hold the whip hand, as it reduces their influence.

In the past, there have been questions about whether standards of corporate governance at foreign-controlled firms, such as the natural resources groups Vedanta and Eurasian Natural Resources Corporation (ENRC), meet basic requirements.

Critics have blamed London's "light-touch" approach to regulation for allowing in so many overseas companies, some from countries without a functioning democracy.

Eric Chalker, director of the UK Shareholders' Association, which represents retail investors, said the link between the FTSE and UK investors had been largely broken. "The index no longer broadly reflects British business interests; to a great extent UK investors have become detached from their investments. Factors which affect share prices are often invisible to shareholders, as they are connected to events that happen far away and may be affected by foreign political considerations," he said.

He also criticised the role played by derivatives speculators who gamble on share price movements "and aren't really interested in the long-term well-being of the business where they have an interest."

Chalker believes investors should be encouraged to invest in British companies and that indices such as the FTSE "should be more orientated towards the needs of UK firms".

Data from the accountants Deloitte shows the FTSE is increasingly made up of non-British firms with 12 big foreign groups, including the miners Xstrata, ENRC and Kazakhmys joining the index since 2001. More than 30% of the index is made up of resources companies, and many of those are domiciled outside the UK.

Robert Talbut, chief investment officer of Royal London Asset Management, does not have a problem with the FTSE representing a wide international mix of groups, as this gives the London "more vibrancy and diversity, which is a good thing".

But he does take issue with firms offering a relatively small free float – the pool of available shares that can be acquired by investors. The Financial Services Authority (FSA), which acts as the UK listing authority, requires a minimum free float of 25% but Talbut says many investors think it should be closer to 50%.

There were raised eyebrows in May when the once secretive Swiss commodities group Glencore launched the biggest ever IPO in London but floated only 12% of the shares. The FSA agreed with Glencore's argument that there were certain mitigating factors that allowed it to get away with such a small free float.

Talbut says: "There is a view that if an [overseas] company lists in London, we should ensure the highest standards of corporate governance are followed and make certain the interests of minority shareholders are protected."

There was uproar in June when two independent directors were ousted from the board of ENRC by controlling shareholders that included two Kazakh millionaires and the Kazakhstan government.

• This article was amended on 7 December 2011. In the text and in a quote the original stated that the London Stock Exchange is the listings regulator. This has been corrected and the quote deleted.